Architectural fountains are generally used for relatively large-scale decoration, such as in open plazas, lobbies, and the like. Their shape is selected to accomplish the architect's artistic objectives, and when in operation are intended to provide a sense of shape and texture. The shape is attained by using nozzles, deflectors, and the like, and the texture is determined by the cohesiveness of the stream, by its content of air bubbles, and by the size of its drops or droplets.
When the droplets are very fine, then the pattern emerges more as a spray which is perceived as a body that can merge on the opaque. It is at the best translucent, and does not sparkle. While this effect may be and sometimes is appropriate for some fountain installations, there is a considerable preference for plumes which have a sparkling clarity, and a sense of body, and which when illuminated give a sparkling, even twinkling display of considerable beauty.
A determinant of the plume which determines whether the display will be a spray, a clear stream, or a sparkling plume is the size of the drops. A spray by definition has very small droplets, and presents a diffuse appearance. At the opposite extreme, a clear cohesive stream has no appreciable droplets, and it appears almost as a rod. It takes illumination poorly.
Another significant determinant in fountain displays is the aeration of the stream. A non-aerated stream has a clear appearance, and does not appear to have much body. While it illuminates acceptably in sunlight, it illuminates poorly at night. A properly aerated stream illuminates well in both sunlight and in artificial lighting, and when the streams are comprised of large droplets that are aerated, an optimally visible fountain display results.
Accordingly, it is an object of this inventon to provide a nozzle whose output includes large numbers of drops of major size, and with substantial aeration of these drops.
It has been found that drops of major size are most advantageously formed by violent agitation of the water stream. While water is readily agitated by spinners, choppers, and the like, it is a useful objective to attain a pattern from an agitated stream with the use of a nozzle which has no moving parts. Such a nozzle is then maintenance free, and is less expensive to manufacture.
It is another object of this invention to provide a nozzle whose output is aerated to improve the display.